JP2015115326A - Power storage device comprising current breaking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage device capable of suppressing malfunctions of a current breaking device by suppressing generation of flexure moment to the current breaking device via a conductive member when an electrode assembly is inserted into a case.SOLUTION: A power storage device comprises: a case; first and second electrode terminals provided on a terminal attachment wall of the case; and an electrode assembly, a first conductive member, a second conductive member, and a current breaking device that are housed in the case. The first conductive member and the second conductive member are connected with a positive electrode or a negative electrode of the electrode assembly respectively . The current breaking device is arranged between the terminal attachment wall and the electrode assembly, and connected in series between the first electrode terminal and the first conductive member to connect or disconnect an energization path from the electrode assembly to the first electrode terminal. A first spacer in contact with the electrode assembly is further provided between the current breaking device and the electrode assembly.

Description

  The present invention relates to a power storage device including a current interrupt device.

  Patent Document 1 describes a lithium battery including a pressure detection type current interrupting device. In this battery, the positive electrode terminal and the negative electrode terminal are attached to the same wall of the case, and the current interrupting device is provided substantially below the positive electrode terminal (on the electrode assembly side). The current interrupting device is connected in series between the conductive member connected to the positive electrode of the electrode assembly and the positive electrode terminal. When the pressure in the battery case increases, the deforming plate of the current interrupting device is deformed, and the energization path between the positive electrode and the positive electrode terminal is interrupted.

JP 2012-119183 A

  In the manufacturing process of the power storage device in which both the positive electrode terminal and the negative electrode terminal are provided on one terminal mounting wall, and the current interrupting device is disposed between the electrode assembly and the terminal mounting wall, the electrode assembly When the electrode assembly and the case are inserted into the case so that the electrode assembly side is the bottom side of the case (the side facing the terminal mounting wall) with the conductive member, the current interrupt device, and the electrode terminal connected, Due to the friction with the inner wall, a reaction force is generated in the direction opposite to the insertion direction. Usually, since there is a gap between the electrode assembly and the current interrupt device, a bending moment may be generated in the conductive member due to this reaction force. When this bending moment is transmitted to a portion that switches between energization and insulation, which is weak in the current interruption device, via the conductive member, there is a possibility that the current interruption device malfunctions and interrupts the energization path.

  The power storage device disclosed in this specification includes a case, an electrode assembly that is housed in the case and includes a positive electrode and a negative electrode, a first electrode terminal and a second electrode terminal that are provided on a terminal mounting wall of the case, and the case. A first conductive member housed and connected to one polarity electrode of the electrode assembly, and a second conductive member housed in the case and connected to both the other polarity electrode of the electrode assembly and the second electrode terminal A member, and a current interrupting device that is connected in series between the first electrode terminal and the first conductive member housed in the case, and that connects or interrupts the energization path from the electrode assembly to the first electrode terminal. Yes. The current interrupting device is disposed between the terminal mounting wall and the electrode assembly. A first spacer contacting the electrode assembly is further provided between the current interrupt device and the electrode assembly.

  The power storage device further includes a first spacer that contacts the electrode assembly between the current interrupt device and the electrode assembly. When the first spacer contacts the electrode assembly, there is no gap between the current interrupting device and the electrode assembly, and a bending moment is generated in the first conductive member due to friction when the electrode assembly is inserted into the case. This can be suppressed. For this reason, it can suppress that an electric current interruption apparatus raise | generates a malfunction and interrupts | blocks an electricity supply path | route.

  In the above power storage device, the first spacer may be fixed to the current interrupt device.

  In the above power storage device, the surface of the first spacer that contacts the electrode assembly may have a shape corresponding to the shape of the surface of the electrode assembly on the first spacer side.

  The power storage device may further include a second spacer that is in contact with the electrode assembly between the second electrode terminal and the electrode assembly. Further, the second spacer may be fixed to the second electrode terminal. Furthermore, the surface of the second spacer in contact with the electrode assembly may have a shape corresponding to the shape of the surface on the second spacer side of the electrode assembly.

  The power storage device may further include a buffer material between the electrode assembly and the wall surface facing the terminal mounting wall of the case.

  The power storage device may be a secondary battery.

  According to the present invention, it is possible to suppress the occurrence of a bending moment in the first conductive member when the electrode assembly is inserted into the case, and as a result, to provide a power storage device that can suppress malfunction of the current interrupt device. be able to.

1 is a longitudinal sectional view of a power storage device according to Embodiment 1. FIG. It is the II-II sectional view taken on the line of FIG. It is a figure which shows notionally the electrode assembly which has the winding structure of FIG. It is a figure which expands and shows the 1st spacer of FIG. It is a figure which expands and shows the 2nd spacer of FIG. It is a figure which expands and shows the electric current interruption apparatus of FIG. 1 and its vicinity, and has shown the state at the time of normal operation of an electrical storage apparatus. It is a figure which expands and shows the electric current interruption apparatus of FIG. 1, and its vicinity, and has shown the state at the time of the overcharge of an electrical storage apparatus. It is a figure which shows the electric current interruption apparatus which concerns on a modification, and its vicinity, and has shown the state at the time of normal operation of an electrical storage apparatus. It is a figure which shows the electric current interruption apparatus which concerns on a modification, and its vicinity, and has shown the state at the time of the overcharge of an electrical storage apparatus. It is a longitudinal cross-sectional view of the electrical storage apparatus which concerns on a modification.

  The power storage device disclosed in this specification can be used as a conventionally known power storage device such as a sealed secondary battery or a sealed capacitor. Furthermore, specific examples of the secondary battery include secondary batteries such as lithium ion batteries, nickel metal hydride batteries, nickel cadmium batteries, and lead storage batteries that are charged and discharged with a relatively high capacity and a large current. The power storage device may be mounted on a vehicle, an electric device, or the like.

  The power storage device disclosed in this specification includes a case, an electrode assembly, a first conductive member, a second conductive member, and a current interrupting device housed in the case, and a first terminal provided on a terminal mounting wall of the case. An electrode terminal and a second electrode terminal are provided. The current interrupting device is disposed between the terminal mounting wall and the electrode assembly. The power storage device further includes a first spacer that contacts the electrode assembly between the current interrupt device and the electrode assembly. The first spacer may be fixed to the current interrupt device. For example, the first spacer and the current interrupt device may be fixed in contact with each other, or may be fixed to each other via another member (for example, the first conductive member).

  The electrode assembly includes a positive electrode and a negative electrode. As the electrode assembly, for example, an electrode assembly including a pair of electrode layers in a state in which a sheet-like positive electrode and a sheet-like negative electrode sandwich a sheet-like separator in between can be mentioned. Can be exemplified by a stacked electrode assembly in which a large number of electrode pairs are stacked, and a wound electrode assembly in which the electrode pairs are wound around a predetermined axis. Either the positive electrode or the negative electrode may be disposed on the outermost side of the electrode assembly, or a separator may be disposed. The electrode assembly may be immersed in the electrolyte.

  The first conductive member is connected to one polarity electrode of the electrode assembly. The current interrupt device is connected in series between the first electrode terminal and the first conductive member. The second conductive member is connected to both the electrode of the other polarity of the electrode assembly and the second electrode terminal. When the first conductive member is connected to the positive electrode, the current interrupting device is installed in the positive-side energization path (the energization path from the positive electrode of the electrode assembly to the first electrode terminal), and the second conductive member is Connected to both the negative electrode and the negative electrode terminal of the electrode assembly. When the first conductive member is connected to the negative electrode of the electrode assembly, the current interrupting device is installed in the negative-side energization path (the energization path from the negative electrode of the electrode assembly to the first electrode terminal), and the second The conductive member is connected to both the positive electrode and the positive electrode terminal of the electrode assembly. The current interrupting device connects or interrupts the energization path from the electrode assembly to the first electrode terminal. The electrode interrupting device may constitute a part of an energization path from the electrode assembly to the first electrode terminal. More specifically, for example, the energization path from the first electrode (positive electrode or negative electrode) corresponding to the first electrode terminal of the electrode assembly to the first electrode terminal is connected in series in this order. It may be electrically connected via a member or a current interrupt device.

  The surface of the first spacer in contact with the electrode assembly may have a shape corresponding to the shape of the surface on the first spacer side of the electrode assembly. Here, “corresponding” means a similar or complementary shape, which allows the surfaces to come into wide contact with each other. For example, when the surface on the first spacer side of the electrode assembly is a flat surface, it is preferable that the shape of the surface of the first spacer in contact with the electrode assembly is a similar flat surface. Further, for example, when the surface on the first spacer side of the electrode assembly is an R-shaped convex surface, the shape of the surface contacting the electrode assembly of the first spacer is a complementary shape, that is, an R having the same curvature. A concave surface having a shape is preferable. When the contact surfaces of the first spacer and the electrode assembly have shapes corresponding to each other, the areas of the contact surfaces are increased, and the contact pressure due to contact can be reduced.

  The first spacer and the surface in contact with the first spacer of the electrode assembly are preferably insulated. In order to insulate, for example, an insulating separator may be disposed on the outermost periphery of the electrode assembly so that the surface in contact with the first spacer of the electrode assembly becomes the separator. The surface in contact with the assembly may be formed of an insulating material, or the entire first spacer may be formed of an insulating material. As the insulating material, an insulating material conventionally used in the field of power storage devices can be used, and a resin material such as polypropylene or polyethylene can be suitably used on the first spacer side.

  A second spacer in contact with the electrode assembly may be further provided between the second electrode terminal and the electrode assembly. In addition to the effect of suppressing the bending moment on the first conductive member side due to the reaction force when the electrode assembly 60 is inserted into the case 1, the bending moment is suppressed on the second conductive member side. Effect can be obtained. Further, when the electrode assembly is inserted into the case, the electrode assembly can be pushed in evenly by both the first spacer and the second spacer. The second spacer may be fixed to the second electrode terminal.

  Similar to the first spacer, the surface of the second spacer in contact with the electrode assembly may have a shape corresponding to the shape of the surface of the electrode assembly on the second spacer side. As described in the first spacer, if the contact surfaces of the second spacer and the electrode assembly have shapes corresponding to each other, the area of the contact surface increases, and the contact pressure due to contact decreases. can do.

  Similarly to the first spacer, it is preferable that the second spacer and the surface in contact with the second spacer of the electrode assembly are insulated. By the same means as used for the first spacer, the second spacer and the surface of the electrode assembly in contact with the second spacer can be insulated.

  In the above power storage device, a buffer material may be provided between the electrode assembly and the wall surface facing the terminal mounting wall of the case. Even when the electrode assembly is inserted deeply into the case when the electrode assembly is inserted into the case, the electrode assembly abuts against the buffer material rather than the wall surface facing the terminal mounting wall of the case. By contacting the buffer material, the reaction force (force acting in the direction opposite to the insertion direction) when inserting the electrode assembly can be reduced.

  FIG. 1 is a cross-sectional view of the power storage device 100 according to the first embodiment. The power storage device 100 includes a case 1, a wound electrode assembly 60, a first conductive member 68, a second conductive member 64, a first electrode terminal 19, a second electrode terminal 119, and a current interrupt device. 120, a first spacer 150, and a second spacer 160. In the following, for convenience of explanation, the positive direction side of the z-axis may be described as the upper side and the negative direction side as the lower side.

  The case 1 is a substantially rectangular parallelepiped box-shaped member, and includes an electrode assembly 60, an electrolyte solution (not shown), a first conductive member 68, a second conductive member 64, a current interrupting device 120, a first, The spacer 150 and the second spacer 160 are accommodated. The upper end surface (the surface on the positive direction side of the z-axis) of the case 1 is a terminal mounting wall, to which the first electrode terminal 19 and the second electrode terminal 119 are mounted. The first electrode terminal 19 is electrically connected to the negative electrode of the electrode assembly 60, and the second electrode terminal 119 is electrically connected to the positive electrode of the electrode assembly 60.

  As shown in FIGS. 2 and 3, the electrode assembly 60 includes a positive electrode sheet 601, a separator 603, a negative electrode sheet 602, and a separator 603 that are wound in this order with the positive electrode sheet 601 side facing inward. It is wound around an axis (r-axis shown in FIGS. 1 and 3). The positive electrode sheet 601 includes an aluminum positive electrode metal foil 601a and a positive electrode active material layer 601b formed on both surfaces of the positive electrode metal foil 601a. The negative electrode sheet 602 includes a copper negative electrode metal foil 602a and negative electrode active material layers 602b formed on both surfaces of the negative electrode metal foil 602a. The separator 603 is an insulating porous body. The electrode assembly 60 is accommodated in the case 1 in a state impregnated with a liquid electrolyte. The r-axis, which is the winding axis of the winding structure, is substantially parallel to the y-axis, and the first electrode terminal 19 and the second electrode terminal 119 are located at both ends of the terminal mounting wall along the r-axis direction. Each is arranged.

  The first conductive member 68 includes a current collector 67, and the negative electrode sheet 602 of the electrode assembly 60 is bundled by the current collector 67. The second conductive member 64 includes a current collector 65, and the positive electrode sheet 601 of the electrode assembly 60 is bundled by the current collector 65.

  As shown in FIG. 1, the first conductive member 68 has a shape in which a flat plate made of copper or a copper alloy is bent, extends below the first electrode terminal 19 in the negative direction of the y axis, and is bent. , Extending in the negative direction of the z-axis.

  As shown in FIGS. 1 and 2, the upper surface 60 a of the electrode assembly 60 is an R-shaped surface that protrudes toward the terminal mounting wall side (the positive z-axis direction side). The first spacer 150, the second spacer 160, and the electrode assembly 60 are in contact with each other at both ends in the y direction of the upper surface 60a.

  The current interrupt device 120 is connected to the first conductive member 68 on the lower surface side, and is connected to the first electrode terminal 19 on the upper surface side. Further, the first electrode terminal 19 and the first conductive member 68 are electrically connected via a current interrupt device 120. As described above, the current-carrying path on the negative electrode side from the negative electrode sheet 602 to the first electrode terminal 19 of the electrode assembly 60 passes through the first conductive member 68 and the current interrupting device 120 connected in series in this order. It is connected.

  The second conductive member 64 has a shape obtained by bending a flat plate made of aluminum, extends below the second electrode terminal 119 in the positive direction of the y-axis, bends, and extends in the negative direction of the z-axis. A current-carrying path on the positive electrode side from the positive electrode sheet 601 to the second electrode terminal 119 of the electrode assembly 60 is connected via a second conductive member 64. The power storage device 100 can exchange electricity between the electrode assembly 60 and the outside of the case 1 via the first electrode terminal 19 and the second electrode terminal 119. The second conductive member 64 does not necessarily mean a single member. A plurality of conductive members may be connected to form the second conductive member 64.

  As shown in FIG. 4, the first spacer 150 has a shape obtained by cutting one circular surface side of a substantially cylindrical member into an R shape. The first spacer 150 is fixed to the current interrupt device 120 so that the R-shaped surface 150a is on the electrode assembly 60 side (the negative direction side of the z-axis). The surface 150a is a surface in contact with the electrode assembly 60, and has a concave R shape (surface 60a) on the terminal mounting wall side so as to correspond to the shape of the surface (surface 60a) on the first spacer 150 side of the electrode assembly 60. Has a similar curvature). The first spacer 150 is provided with a through hole 151 penetrating in the z direction.

  As shown in FIG. 5, the second spacer 160 has a shape obtained by cutting one circular surface of a substantially cylindrical member into an R shape. The second spacer 160 is fixed to the second electrode terminal 119 so that the R-shaped surface 160a is on the electrode assembly 60 side. The second spacer 160 is a hollow member, and the bolt 119 a of the second electrode terminal 119 extends until it contacts the bottom surface inside the second spacer 160. The second spacer 160 is fixed to the second electrode terminal 119 and the terminal mounting wall by engaging with the terminal mounting wall of the case 1 at the upper part thereof. The surface 160a is a surface in contact with the electrode assembly 60, and has a concave R shape (surface 60a) on the terminal mounting wall side so as to correspond to the shape of the surface (surface 60a) on the second spacer 160 side of the electrode assembly 60. Has a similar curvature). The first spacer 150 and the second spacer 160 are made of an insulating resin material.

  FIG. 2 shows a state where the surface 160a of the second spacer 160 and the surface 60a on the second spacer side of the electrode assembly 60 are in contact with each other. The surface 60a has a convex R shape on the terminal mounting wall side, and the surface 160a has a concave R shape on the terminal mounting wall side so as to correspond to the shape of the surface 60a. For this reason, the whole surface 160a and the whole surface 60a contact, the mutual contact area becomes large, and the surface pressure by contact can be made small. Although not shown, the surface 150a of the first spacer 150 has a shape corresponding to the shape of the surface of the electrode assembly 60 on the first spacer 150 side. The contact area with the surface on the 1 spacer 150 side is increased, and the surface pressure due to contact can be reduced.

  As shown in FIG. 6, the current interrupt device 120 includes a deformation plate 33, a contact plate 35, and an annular member 37. The deformation plate 33 is a diaphragm made of copper or a copper alloy, and is a substantially flat plate-like member that is circular when viewed in plan, and has a truncated cone-shaped convex portion at the center. During normal operation of the power storage device 100, the convex portion of the deformation plate 33 is convex toward the side where the first conductive member 68 and the electrode assembly 60 are disposed (the negative direction side of the z axis). The contact plate 35 is a substantially flat plate-shaped metal member that is circular in plan view, and has a flat plate-shaped central portion and a side surface portion that curves and extends from the central portion toward the deformable plate 33. The annular member 37 is an annular member in plan view. The deformation plate 33 and the contact plate 35 are in contact with each other at the connection portion 34 and are fixed by welding. A wall that separates the space 40 from the electrode assembly 60 side in the case 1 is formed by the deformation plate 33 and the contact plate 35, and the upper surface (the surface on the positive side of the z axis) of the deformation plate 33 and the contact plate 35. The lower surface (the surface on the negative direction side of the z-axis) faces the space 40.

  The contact plate 35 is in contact with the first electrode terminal 19 and is fixed by welding. The deformation plate 33 is fixed to each other by welding while being sandwiched between the annular member 37 and the contact plate 35. Further, the deformable plate 33 is in contact with the first conductive member 68 at the joint portion 41 and is welded to the first conductive member 68. The first conductive member 68 has a circular hole 68a formed along the circular lower surface of the convex portion of the deformable plate 33, and the joint 41 is located around the hole 68a. . The annular member 37 is fixed in an insulated state from the first conductive member 68 by an insulating adhesive such as a silicon-based adhesive. The first conductive member 68, the deformation plate 33, and the contact plate 35 are connected in series in this order from the electrode assembly 60 toward the first electrode terminal 19, and these members constitute a current-carrying path on the negative electrode side. Has been. The first spacer 150 is fixed below the first conductive member 68 with an adhesive or the like so that the through hole 151 is directly below the hole 68a (the negative direction of the z axis). The first spacer 150 is fixed to the current interrupt device 120 through the first conductive member 68.

  Since the upper surface of the deformation plate 33 faces the space 40 and the lower surface faces the electrode assembly 60 side in the case 1 through the through hole 151, the pressure on the electrode assembly 60 side in the case 1 is When the pressure rises and the space 40 side has a negative pressure with respect to the case 1 side, the deformation plate 33 is reversed in the direction away from the first conductive member 68 (the positive direction of the z-axis) as shown in FIG. When the deformable plate 33 is reversed and the joint portion 41 is peeled off from the first conductive member 68, the energization path on the negative electrode side is interrupted.

  In the manufacturing process of the power storage device 100, the electrode assembly 60 side is connected to the bottom surface side of the case 1 (the terminal mounting wall When it is inserted into the case 1 so as to be on the opposite side, it is opposite to the insertion direction (the negative direction of the z axis) and the reverse direction (the positive direction of the z axis) due to friction between the electrode assembly and the inner wall of the case. Force acts. If there is a gap between the electrode assembly 60 and the current interrupt device 120, a bending moment may be generated in the first conductive member 68 by this reaction force. When this bending moment is transmitted to the current interrupting device 120 via the first conductive member 68, the current interrupting device 120 is weak, and the portion for switching between energization and electrical insulation (the deformed plate 33 and the first conductive member 68 are welded to each other). It is possible that a load is applied to the joined portion 41), causing the current interrupt device 120 to malfunction and interrupting the energization path on the negative electrode side.

  In the power storage device 100, a first spacer 150 that is in contact with the electrode assembly 60 is provided between the current interrupt device 120 and the electrode assembly 60. Since the first spacer 150 is in contact with the electrode assembly 60, there is no gap between the current interrupt device 120 and the electrode assembly 60. Therefore, the first spacer 150 may be affected by the reaction force when the electrode assembly 60 is inserted into the case 1. Generation of a bending moment in the conductive member 68 can be suppressed. For this reason, it can suppress that the electric current interruption apparatus 120 raise | generates a malfunctioning and interrupts | blocks the electricity supply path | route on the negative electrode side.

  In addition, the power storage device 100 includes a second spacer 160 that is in contact with the electrode assembly 60 between the second electrode terminal 119 and the electrode assembly 60. For this reason, the bending moment which generate | occur | produces in the 2nd conductive member 119 side by the reaction force at the time of inserting the electrode assembly 60 in the case 1 can be suppressed. Further, when the electrode assembly 60 is inserted into the case 1, the electrode assembly 60 can be pushed in evenly by both the first spacer 150 and the second spacer 160.

(Modification)
In the above-described embodiment, the case 1 is a box-shaped member having a substantially rectangular parallelepiped shape. However, the case may be a box-shaped member having a substantially cylindrical shape, for example.

  In the above-described embodiment, the current interrupting device 120 has one surface of the deformable plate 33 having the joint portion 41 exposed to the pressure in the case 1, and the pressure in the case 1 rises. Although it is reversed when the pressure difference between both surfaces of 33 becomes a predetermined value or more, it is not limited to this. For example, as in the current interrupting device 220 described below with reference to FIGS. 8 and 9, the pressure in the case 1 is increased in the first deformable plate 5 (an example of the deformed plate) joined to the first conductive member 68. The second deformation plate 3 (an example of a deformation plate) that is sometimes reversed may be deformed by receiving a load applied thereto, thereby interrupting the energization path. Further, the member to be joined (for example, the first conductive member) to be joined to the deformable plate may be cut while maintaining the joining without being divided by peeling when the current is interrupted. In the following description of the modified examples according to FIGS. 8 and 9, only parts different from the power storage device 100 of the first embodiment will be described, and redundant description of the same configuration as the power storage device 100 will be omitted.

  The current interrupt device 220 includes a first deformable plate 5, a second deformable plate 3, insulating resin O-rings 14 and 17, support members 11 and 20, and a protrusion 12. In the current interrupting device 220, the energization unit 4 provided at the end of the first conductive member 68 is inserted. The first deformation plate 5 is electrically connected to the first electrode terminal 19 through the sealing lid body 7. The first deformation plate 5, the energizing portion 4, and the second deformation plate 3 are arranged in this order in the direction from the first electrode terminal 19 side to the electrode assembly 60 side (the direction from the top to the bottom in FIG. 8). ing. An O-ring 17 is sandwiched between the first deformable plate 5 and the energizing portion 4, and an O-ring 14 is sandwiched between the energizing portion 4 and the second deformable plate 3. A space 240 is formed by the second deformation plate 3, the first deformation plate 5, the O-rings 14 and 17, and the support members 11 and 20.

  The second deformable plate 3 is a diaphragm made of copper or a copper alloy, and is fixed to the outer peripheral portion by the support member 11 and is sealed from the electrode assembly 60 side in the case 1 by the O-ring 14. An insulating projection 12 is provided at the center of the second deformable plate 3 so as to project toward the energizing portion 4 side. The protrusion 12 has a cylindrical shape, and the surface on the current-carrying part 4 side is the contact part 24. The lower surface side of the second deformation plate 3 facing the surface on which the protrusions 12 are installed is a planar pressure receiving portion 22.

  The central portion 15 of the energization portion 4 of the first conductive member 68 is formed thin. The central portion 15 is located above the contact portion of the protrusion 12 of the second deformable plate 3, and a fracture groove 16 is formed on the lower surface thereof. The upper surface of the central portion 15 is the joint portion 6. The energization part 4 is in contact with the first deformation plate 5 at the joint part 6.

  The first deformable plate 5 is a diaphragm made of copper or a copper alloy, and is fixed by a support member 11 at the outer peripheral portion. The first deformable plate 5 is in contact with the joint portion 6 of the energization portion 4 at the joint portion 23 on the lower surface of the central portion. The joining part 6 of the energizing part 4 and the joining part 23 of the first deformation plate 5 are fixed to each other by welding and are electrically connected.

  The first spacer 260 is fixed below the second deformation plate 3. The upper surface of the first spacer 260 has a shape corresponding to the shape of the lower surface of the second deformation plate 3. The lower surface of the first spacer 260 (the surface in contact with the electrode assembly 60) is the surface of the electrode assembly 60 on the first spacer 260 side (the surface 60a shown in FIGS. 1 and 2), like the first spacer 150 of the first embodiment. ). The first spacer 260 is a substantially annular member having a through hole in the center thereof when viewed in a plan view, and is formed of an insulating material. The first spacer 260 is fixed to the current interrupt device 220 so that the through hole is located below the pressure receiving portion 22 of the second deformation plate 3. The pressure receiving portion 22 faces the current assembly 60 side in the case 1 through the through hole of the first spacer 260.

  An insulating sealing member 10 is mounted between the upper surface of the sealing lid 7 and the inner surface of the case 1, and the sealing lid 7 and the case 1 are electrically insulated. The support member 11 is insulative, is formed by a resin mold, and is formed in a ring shape with a substantially U-shaped cross section. With the substantially U-shaped inner surface of the support member 11, the outer periphery of the first spacer 260, the outer periphery of the second deformation plate 3, the O-rings 14 and 17, the outer periphery of the energization unit 4, and the outer periphery of the first deformation plate 5 And the outer peripheral part of the sealing lid 7 are sandwiched in a laminated manner and are integrally held. The O-rings 14 and 17 and the support member 11 are insulative, the second deformable plate 3 and the energizing portion 4 are insulated, and the energized portion 4 of the first deformable plate 5 and the first energizing member 68 are joined. The parts other than the parts 6 and 23 are insulated. The outer surface of the support member 11 is covered with a metal caulking member 20 to ensure sealing and holding. Further, the inner surface portion of the sealing lid body 7 is a concave portion 18 that is recessed upward, and forms a space 240 when the first deformation plate 5 is deformed upward by the protrusions 12 of the second deformation plate 3.

  From the electrode assembly 60 toward the first electrode terminal 19, the energization part 4, the first deformation plate 5, and the sealing lid body 7 of the first conductive member 68 are connected in series in this order. The first electrode terminal 19 and the first conductive member 68 are electrically connected via the first deformation plate 5 of the current interrupt device 220. During normal operation of the power storage device, the contact portion 24 of the protrusion 12 is not in contact with the energization portion 4 as shown in FIG. That is, the energization path on the negative electrode side is connected.

  When the power storage device is overcharged, as shown in FIG. 9, the second deformable plate 3 is deformed toward the energizing portion 4, and the abutting portion 24 of the protrusion 12 abuts on the lower surface of the central portion of the energizing portion 4 to energize. The portion 4 is broken at the breaking groove 16, and the central portion of the energization portion 4 is separated from the energization portion 4. As a result, the joining portion 6 and the joining portion 23 are separated from and separated from the energizing portion 4, the electrical connection between the current interrupting device 220 and the first conductive member 68 is interrupted, and the energizing path on the negative electrode side is interrupted. Is done.

  In another modification, even if a buffer material 190 is installed between the electrode assembly 60 and the wall surface facing the terminal mounting wall of the case 1 as in the power storage device 100a shown in FIG. Good. As a material of the buffer material 190, a resin material having insulation and elasticity can be suitably used. The configuration other than the buffer material 190 of the power storage device 100a is the same as that of the power storage device 100 shown in FIG. Even when the electrode assembly 60 is inserted deeply into the case 1 when the electrode assembly 60 is inserted into the case 1, the electrode assembly 60 contacts the elastic cushioning material 190. The reaction force generated by the contact can be reduced as compared with the case where the contact is made with the wall facing the terminal mounting wall.

  In addition, in said Example and modification, although the electric current interruption apparatus was arrange | positioned on the electricity supply path | route on the negative electrode side, you may arrange | position a electric current interruption apparatus on a positive electrode electricity supply path | route. The first spacer may not be fixed to the current interrupt device. Similarly, the second spacer may not be fixed to the second electrode terminal.

  Further, the surface of the first spacer in contact with the electrode assembly may not have a shape corresponding to the shape of the surface on the first spacer side of the electrode assembly. For example, when the surface of the electrode assembly on the first spacer side has an R shape as shown in FIG. 2, the surface of the first spacer that contacts the electrode assembly may be a flat surface. Similarly, the surface of the second spacer in contact with the electrode assembly may not have a shape corresponding to the shape of the surface on the second spacer side of the electrode assembly.

  As mentioned above, although embodiment and the Example of this invention were described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

1: Case 3: 2nd deformation board 4: Current supply part 5: 1st deformation board 6, 23, 41: Joining part 19: 1st electrode terminal 33: Deformation board 35: Contact board 60: Electrode assembly 64: 2nd Conductive member 68: first conductive member 100, 100a: power storage device 119: second electrode terminals 120, 220: current interrupt device 150, 260: first spacer 160: second spacer 601: positive electrode sheet 602: negative electrode sheet 603: separator

The power storage device disclosed in this specification includes a case, an electrode assembly that is housed in the case and includes a positive electrode and a negative electrode, and a first electrode terminal that is provided on a terminal mounting wall that is one of a plurality of walls constituting the case. And the second electrode terminal, the first conductive member housed in the case and connected to one polarity electrode of the electrode assembly, the other polarity electrode housed in the case and the second electrode terminal of the electrode assembly Between the first electrode terminal and the first conductive member. The second conductive member connected to both of the first conductive member, the terminal mounting wall, and the electrode assembly are disposed between the second conductive member and the first electrode terminal and the first conductive member. And a current interrupting device for connecting or interrupting an energization path from the electrode assembly to the first electrode terminal, and a first spacer disposed between the current interrupting device and the electrode assembly . The current interrupt device includes a deformation plate having a pressure receiving portion that receives the pressure in the case, and when the pressure in the case acting on the pressure receiving portion increases and the deformation plate is deformed, the current path is interrupted. It is configured. A through hole is formed in the first spacer, and the pressure in the case acts on the pressure receiving portion of the deformation plate through the through hole.

In the above power storage device, the first spacer is disposed between the current interrupt device and the electrode assembly . Accordingly, it is possible to suppress a bending moment from being generated in the first conductive member due to friction or the like when the electrode assembly is inserted into the case. For this reason, it can suppress that an electric current interruption apparatus raise | generates a malfunction and interrupts | blocks an electricity supply path | route. Moreover, since the 1st spacer is formed with the through-hole, the pressure in a case can act on the pressure receiving part of the deformation | transformation board of an electric current interruption apparatus through a through-hole.

Claims (8)

Case and
An electrode assembly housed in the case and comprising a positive electrode and a negative electrode;
A first electrode terminal and a second electrode terminal provided on a terminal mounting wall of the case;
A first conductive member housed in the case and connected to one polarity electrode of the electrode assembly;
A second conductive member housed in the case and connected to both the electrode of the other polarity of the electrode assembly and the second electrode terminal;
A current interrupting device that is accommodated in the case and connected in series between the first electrode terminal and the first conductive member, and connects or interrupts an energization path from the electrode assembly to the first electrode terminal; With
The current interrupting device is disposed between the terminal mounting wall and the electrode assembly;
A power storage device, further comprising a first spacer in contact with the electrode assembly between the current interrupt device and the electrode assembly.   The power storage device according to claim 1, wherein the first spacer is fixed to the current interrupt device.   3. The power storage device according to claim 1, wherein a surface of the first spacer that contacts the electrode assembly has a shape corresponding to a shape of a surface of the electrode assembly on the first spacer side. .   The power storage device according to claim 1, further comprising a second spacer that is in contact with the electrode assembly between the second electrode terminal and the electrode assembly.   The power storage device according to claim 4, wherein the second spacer is fixed to the second electrode terminal.   6. The power storage device according to claim 4, wherein a surface of the second spacer that contacts the electrode assembly has a shape corresponding to a shape of a surface of the electrode assembly on the second spacer side. .   The power storage device according to claim 1, further comprising a buffer material between a wall surface of the case facing the terminal mounting wall and the electrode assembly.   The power storage device according to any one of claims 1 to 7, wherein the power storage device is a secondary battery.

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